Adjustable suspension for vehicles



April 8, 1952 Filed Deo`. 13. 1947 J. P. BUTTERFIELID ADJUSTABLESUSPENSION FOR VEHICLES 2 SHEETS-SHEET l l JNVENTOR. 1755K vffcrf'e la7.

April 8f 1952 J. P. BUTTERFIELD .2,592,539l

ADJusTABLmsUsPENsIoN FOR VEHICLES Filed Deo. 1s, 1947 2 SHEETS-.SHEET 2A JNVENTOR. g f/ -c/n Pwffef/ze/J BY S Patented Apr. 8, 1952 ADJUSTABLESUSPENSION FR VEHICLES John P. Butterfield, Grosse Pointe Woods, Mich.,assignor to Chrysler Corporation, Highland Park, Mich., a corporation ofDelaware Application December 13, 1947. Serial No. 791,616

1o claims. l

This application relates to an adjustable suspension for a vehicle. Morespecifically it relates to a suspension, in which adjustment is madethrough hydraulic means.

Problems arise in the provision of a satisfactory suspension for avehicle in which the ratio of vehicle-body load plus carried load suchas passengers to vehicle-body load is relatively high. If the suspensionsprings are soft enough for a good ride when the total load isrelatively low. the deection of the springs -at full load may be higherthan desirable. If the suspension springs are stiff enough to keep thedeflection to satisfactory limits, the ride at light loads may beuncomfortable.

An object of the present invention is to provide an improved vehiclesuspension in which adjustment is made at heavy loading to compensatefor a relatively great deflection oi springs. The adjustment may becarried out by hydraulic means.

Another object is the provision of an hydraulic means for use in anadjustable suspension for a vehicle. This hydraulic means may be closelyassociated with an hydraulic shock absorber for the vehicle suspension.

Other objects will appear from the disclosure.

In the drawings:

Fig. 1 is a sectional View through the upper half of the improvedsuspension of the present invention;

Fig. 2 is a section through the .lower half of the suspension;

Fig. 3 is a section taken on the line 3--3 of Fig. 1;

Fig. 4 is a section taken on the line 4 4 of Fig. l; and

Fig. 5 is a section taken on the line 5-5 of Fig. 3.

Reference character I designates a head, which has a ring portion I`Iadapted to be secured to a member, not shown, associated with thevehicle body. The reference character I2 designates aring adapted to beassociated with Wheels for the vehicle. Between the ring portion II andthe ring I2, or between the vehicle body and the vehicle wheels, islocated the novel suspension `of the; present invention, which is aboutto be described.

The head I0 is secured to a body I3 by means of a plurality of screwsI41. The body I3 has a large central cylindrical opening I4 reduced atits lower end by a shoulderA I1, as seen in Fig. 1. This cylindricalopening I4 may be termed a resv. ervoir or chamber, because it isadapted to store fluid used for lifting purposes as will be describedpresently.

Surrounding the storage chamber I4 in spaced relation are threeCylindrical openings I5, as seen in Figs. 1 and 4. Each of the openingsI5 slidably houses a lifting piston It having at its upper side a sealIl and at its lower side a rod IS projecting through the base of thehousing I3 and a seal Iiia contained in the base into engagement with aring I9. A passage 26 leads from the base of the chamber formed by theopening I5 to the base of the storage chamber I4. A passage 2l leadsfrom the seal lila to the base of the storage chamber I4. A cylindricalbore 22 formed in the housing I3 contains a piston valve having a head23 that is smaller than the bore 22 so as to fit quite loosely therein,and a rubber seal 24 on the piston head fitting closely within the bore22. A rod 25 projects from the head 23 through the housing I3 below thebase of the bore 22 and through a seal 26 carried by the housing. A coilspring 2l acting between the head I9 and a dished member 23 resting onthe seal 24 urges the seal 24 and the piston 23 to the low positionshown in Fig. 1. A passage 23 connects the bases of the bore 22 and thestorage chamber I4. As seen in Fig. 5. a bore 3B formed in the body I3houses a piston 3| which ts the bore snugly. The piston 3l has seals 32and 33 at its upper and lower sides and a rod 34 projects from thepiston through the body I3 at the base of the bore 30 and through a seal35. The lower end of the rod 34 is formed as an enlarged head 35. A coilspring 31 positioned in the bore 30 acts between the seal 33 and thebase of the bore 33 to urge the piston 3l and its rod 34 to the highposition shown in Fig. 5.

The head Ill has a central vrecess 38 extending in alignment with thecentral bore I4 formed in the body I3 to close the upper end of the storage chamber. A narrow passage 39 is aligned with and extends from thebore 22 and above it there is a larger passage 4i] joined to the passageY 39 by a seat 4I, which is shown in Fig. 1 to be closed by a ball valve42 under the influence of a coil spring 43. The upper end of the coilspring 43 is engaged by a threaded plug 44 mounted in the head Iadjustable so as to control the pressure exerted by the coil spring 43upon the ball valve 42. As seen in Fig. 3, the passage 40 is intersectedby a passage 45, which may be formed by drilling, in an operationthrough which access for the drilling tool is had through a flangedthreaded opening 46 formed on the head I0 and closed by a plug 4l. Thepassage 45 intersects not only the passage 40 but also bores 48 formedin the head I as extensions of the bores I5 in the body I3.

A bore 4B, which may also be formed by a suitable tool applied to thehead I0 through the opening 46 connects the recess 48 adjacent theopening 46 and another recess 4S. The bore 49 also intersects arelatively small verticalpassage 50 joined by a shoulder with arelatively large passage 52. The shoulder 5| serves as a seat for a ballvalve 53 urged to closing position by a coil spring 54 acting betweenthe ball valve '53r .and the inside of the base of a cup 55 having anopening 56 formed in the base.

The passage 52 in the head I6 communicates with the upper end of thebore 33 in the body I3, although the two are not axially aligned. Asmall passage 51, also in the head I8, communicates with the upper endof the bore 30. 'The'small passage 5'I is joined by a shoulder 58 with alarger pa-ssage`59. An opening 68 joins the passage 59 with the recess38. Shoulder ESser-Vesasfavseat for aball valve 6| urged to closingposition by a v-coilspring 62,-which acts between the ballvalve andaplug 63 threaded in the vheadr Il soas to be- YVadjustable withrespecttheretoand thereby to adjust the pressure of the spring 62 Yuponthe ballvalve 6l.

4As previously stated, the lower ends v`of the pistonrods I8 engage ringI9, -which may be seen in Fig. 1 to rest upon the upper end of a coilspring 64. The lowerend of this spring rests in a' flanged member 65bonded to a tube 66 forming part of a shock absorber. The tube 66is-bonded to a base 61, in turn bonded to the ring I2. A rod 68 is 1bolted to the base 61 by a threaded reduced portion 69 0n the lower endof the rodextending through thebase 61 andra nut 70 engaging thethreaded end. The upper end of the rod 68 carries-a shock-absorberpiston, which is not shown in detail, but which, it is to be understood,may

-have Valve-controlled passages bywhich ow of fluid in two directionsthrough the piston is regulated. The piston 69 is slidably mounted ina1ining- 'I8 on the inside of a tube 1I mounted in another tube '|2. Thetwo tubes are fastened to one another as by ashrinkfit, andthe outertubeis attached to the body I3 throughengagement of a threaded portionI3 on the upper end of the tube with the body I3. Thelower end ofthetubes 'IIY and 'I2 are `fastened to a fitting' 14- slidably receivingthepistonrodf 68. -rFitting '|4contains a seal I5 through'which thepiston rod 68 passes. AA flanged member'IS clamped lbetween the outertube I2l andthe fitting I4-slidably engages `the tube 66 and carries arubber bumper member l1.

A cupped member 'I8 latched to the flanged member "I6 byV a ring'IEIcarries. a rubber. bumper essentiallythepiston 69 and the. tube set'II-'I2 -in which the piston moves is conventional. Fluid above andbelowthe piston 69 passes through the piston when suiicient force is appliedtending. to

:move thebody and the wheels toward or away 1 from one another.

The force must vbe suicient to open the valve passages through .the,piston 69 against the resistance of appropriate springs. Forappropriate shock-absorber action, the resistance to iiow of fluidthrough the piston may be different in one direction from what it is inthe opposite direction. The shock absorber is positioned within thesuspension spring 64 and acts in parallel with it.

`It is intendedv thatthere be sufficient fluid at least partially tofill the Israge chamber I4,

"ring 8|.

. a certain amount.

which is positioned as an axial extension of the shock-absorber tubes'II and l2. As the load upon the vehicle body is increased, thesuspension spring 64 is compressed causing the upper end of the spring,the ring I9, the body I3, and the head I6 to movedownward toward thelower end of the Vspring 64 andthe wheel-connected member I2.

When sufficient compression of the spring 64 has taken place, the end ofthe rod 25 engages the Now when relative reciprocation of the memberssupported on the upper end of the sus- :pension`springi64 takesplacewith respect to the `lower end ofthe springand ythe wheels, because of.bounce or jounce, for example, the piston 23 and associated seal 24reciprocatein the bore 22 because of the. action ofthe coil `spring 21and .repeated .engagement of the valve rod 25 with the ring 8|.v.Duringythis reciprocation, upward movement of the piston.23andassociated seal 24 .moves .uid abovethejpiston. and seal upwards pasttheball valve 42 which islifted from its seat 4I, throughthe .bores45and49 into ythe, recesses 1.48: and the cylindricalopenings I5. Thiscauses the lifting pistons I5. to move downwards in thecylindricalopenings I5, or, since the pistons I6 are prevented frommoving downward because of engagement of .their associated rods I8 withthe ring I9 resting on the upperendof the suspension Aspring 64, thehousing I3, and the head IIlmove upward, aiso movingthe body` upward. Tocontinue with thedescription of the reciprocation ci the piston 23,downward movement thereof does not force fluid. below the .piston outthrough the opening 29 into the chamber I4, because the piston` 23 isloose in the borev 22 andthe periphery of the. associated seal 24 bendsupwards. to allow fluid below the piston 26 to pass aboveV thev piston.This in effect constitutes .a re-loading of the space between the piston23 and the ball valve 42 with uid. .During continued reciprocation ofthe .piston 23 'each upward movement of the piston raises the body I3,head I0, and the vehiclebody Eventually; a condition is reached in whichthe body I3 is raised sufficiently for thezend of thepiston rod 25 nolonger to contact the ring 8| during the aforementioned vre-;ciprocation dueto jounce `or .bounceand.the

f expansion .of thespringi 64hastaken place, and f-.perhapsbecausethebody I3 may previously have 'been' elevatedwithrespect to the upper endof `the spring64 through reciprocation of the piston `23,J.the enlargedheadonthe rodi 34 moves k.upward intocontactwiththe ring 8 I. When thishas happened, any relative reciprocation due to jounce or bounce willcause. the piston 3| to be reciprocatedin-the bore. vInthisreciprocation :downward-movement of. the piston 3| .will draw iiuid.into-the bore 30 abovethe lpiston 3| by opening theball valve 53,becausethe pressure beneath theball valve.53,ini thebore 3i] is reducedbelow that above ,the ballvalve .maintainedbylthe load of the vehicleacting on the uid above the pistons I 6. Upward movement of the piston3| forces open the ball valve 6| and pumps uid above the piston 3|through the passage 59 and the opening 60 back into the storage chamber|4. Continued reoiprocation through the pumping action of the piston 3|decreases the amount of fluid above the pistons I6 and lowers thevehicle body, the head Ill, and the body I3 with respect to the upper.end of the suspension spring 64. When suicient lowering has takenplace, the enlarged head 36 on the valve rod 34 no longer contacts thering 8| during reciprocation, and the pumping action of the piston 3|ceases.

The aforedescribed lifting and lowering apparatus is of special valuefor a vehicle that 1s to be subjected to loads of such a kind that aratio of load plus body Weight to body weight is relatively high. In acase like this if the suspension spring is made relatively sti to limitthe total deection upon full load, the spring may provide too hardriding at light loads. If, on the other hand, the suspension spring ismade relatively soft, the total deflection at full load may be veryhigh. With my device it is possible to use the relatively soft springand to compensate for the large total deflection of the spring at fullload by shifting the body with respect to the part of the spring withwhich the body is associated.

I claim:

l. In a suspension, a iirst part. a second part, coiled resilient meanssupporting the second part for reciprocative movement on the rst part, athird part, and an hydraulic lift device adjustably supporting the thirdpart on the second part, said hydraulic lift device comprising meansforming a liquid chamber between the second and third parts, a pump onthe third part having an input member disposed within the coils of thecoiled resilient means and projecting in the direction of the rst partfor energy receiving engagement therewith and being responsive toreciprocal movement of said third and second parts relative to said rstpart under a condition of heavy load on the resilient means for pumpingliquid into the chamber, and a similar pump responsive to reciprocalmovement of said third and second parts relative to said rst part undera condition of light load on the resilient means for pumping liquid outof the chamber.

2. In a suspension, a iirst part, a second part, coiled resilient meanssupporting the second part :for reciprocative movement on the rst part,a third part, and an hydraulic lift device adjustably supporting thethird part on the second l part, said hydraulic lift device comprisingmeans forming a liquid chamber between the second and third parts, apump on the third part having an input member disposed within the coilsof the coiled resilient means and projecting in the direction of theiirst part for energy receiv- K ing engagement therewith and beingresponsive to reciprocal movement of said third and second partsrelative to said rst part for pumping liquid into the liquid chamber tochange the spacing of the third part in one direction with rebasemember. a rod secured to the base member, a valved piston secured to therod at a region spaced from the base member, a sleeve secured to thebase member and extending therefrom in spaced surrounding relation tothe rod and piston, a spring bracket secured to the exterior of thesleeve at a region adjacent the base member, and a ring secured to theinside of the end of the sleeve remote from the base member; a secondunit comprising a liquid housing, a cylinder secured to the housing andextending therefrom so as slidably to receive the piston and to beslidably received in the interior ring attached to the sleeve, an endstructure on the end of the cylinder remote from the housing slidablyreceiving the piston .rod in sealing relation and being slidablyreceived in the sleeve and rubber bumpers attached to the end structureand being engageable With the interior ring on the sleeve and the basemember upon movement oi the second unit to extreme positions withrespect to the rst unit; a coil spring surrounding the sleeve and havingits lower end resting on the spring bracket attached to the sleeve; aplurality of pistons slidably mounted in the liquid housing and aplurality of rods attached to the pistons and projecting from thehousing toward the coil spring so as to act against the upper endthereof; a iirst pumping means associated with the housing for movingthe pistons and rods with respect to the housing in a direction towardthe coil spring so as to shift the housing away from the base member ofthe iirst unit, said iirst pumping means including a first memberprotruding from the housing and engageable with the ring on the sleeveat a condition of high compression of the spring so as to effect apumping action through reciprocation of the rst member in contact withthe ring; and a second pumping means for moving the pistons and rodswith respect to the housing in a direction away from the coil spring,said second pumping means including a second member protruding from thehousing through the ring on the sleeve and having a head engageable withthe ring at a condition of low compression of the spring so as'to eiecta pumping action through reciprocation of the second member in contactwith the ring.

4. In a suspension, a first unit comprising a spring support and a iirsthydraulic-shock-absorber part, spring means engaging the spring support,a second unit comprising a second hydraulic-shock-absorber partcooperating with the aforesaid rst part, a liquid housing'a'ttached tothe aforesaid second part and having a chamber combined with theaforesaid second part to form a storage reservoir, `rlrst, second, andthird cylinders, a rst passage between the upper ends of the rst andsecond cylinders, a rst valve cooperating with the first passage so asto permit liquid flow through said first passage only from the firstcylinder to the second cylinder, a second passage between the upper endsof the second and third cylinders, a second valve cooperating with thelsecond passage so as to permit liquid ow through said second passageonly from the second cylinder to the third cylinder, a third passagebetween the upper ends of the third cylinder and the chamber, a thirdvalve cooperating with the third passage so as to permitliquid owthrough said third passage only from the third cylinder to the chamber,a fourth passage between the lower portions of the chamber and thecylinder, and having valve means and an extension engageable with; thefirst unit upon heavy loading of the springmeans so as viso-cause rela-;tive reciprocal-movement Vof the rstandsecond .units to reciprocate thefirst piston thereby pumping liquid from the chamber through the fourthpassage, the rst cylinder.. and the first passage `to vthe secondcylinder, a second piston .slidably mounted inthe second cylinder andhaving an extensionengaging the spring means .and being forced downwards'in thesecond'cylinder bythe aforesaid introduction of .liquid'intothesecond cylinder by pumping action of therst piston and Vthereby .actingthrough "engagement Vof fthe second-pistonextensionrwith the. springinea-ns to raise the housing with respect to the irst unit,

and a third piston slidablymounted in theY third y cylinder' and havinganl extension engageable with the first unitatiaicondition oflightloading of the spring means and elevation: of .the housing withrespect tothe'frst unitfsov as tocause rela--V tive'reciprocal movementof the first and second units to reciprocate thev third piston .therebypumping liquid from the second cylinder through the second passage tothe third cylinder and through thethird passage to the reservoir cham--ber, theA housing thus being permitted to ibe lowered with respect to.the secondfpiston and the first unit.

. 5. vIna suspension; a firstL part, .a second part,

a. .spring :carrying .ther second part by` the .rst 1 part, anhydraulicshock. absorber acting between the. parts .in parallel with the spring;a housing having a chamberl communicating with `the shock f absorber, aplurality of lifting cylinders,. an inlet cylinder, andan outletvcylinder,.liiting pistons 1 inthe lifting.` cylinders havingrodsiprojecting from the housing into. engagement with the second part,an inlet valve piston in the inlet cylinder for controlling iiowof.liquid from' the .chamber to the *liftingy cylinders' to. shift. the.liftingv pistons for elevating the 'housing 1 with respect. to thesecond part,` a rod connected tothe inlet valve pistonandrprojectingirom the housing into engagement with therst part underacondition of heavy lloading imposed on the. housing, a spring actingagainst theinlet valve pistonto make it pumpliquid from the chamber'intothe lifting cylinders byreciprocating upon relative reciprocationvbetween the first ,part and the housing at theisaidcondition Vofheavyloading, an, outlet valve piston inthe outiet cylinder forcontrollinglow of liquidfrom the lifting cylinders to the chamber toshift :the lifting 'pistons for. loweringithehousing with .respect tothe V.second part,.a rod. connected to the outlet valve .piston andprojecting .from thezhousing intoen gagement with the first part under acondition of light loading imposed on .the housing,- and a spring actingagainst ,the outlet valve piston to make it pump liquid from Athe.lifting cylinders to the chamber by reciprocatingupon relative recipro-.cation between thefrst part. and .the housing at the said condition of.light loading imposed on 'the housing.

`.6.'In combination,..a load-carrying supported part, a partforsupportlng saidloadcarrying supported part, a compression springloadmem- `ber. and a shock absorber member disposed axially therewthin,said members each being mountedat one end to said supporting part andsaid shock absorber -member having its opposite end connected to saidload-carrying supported part, and automaticimeans operativelyassociatingthe opposite. end .of the. compression spring. and load- 4carryingsupported part for maintainingwithin limits .a predetermined" -net.spacing between the ysupported and supporting-parts irrespective. oi

theY particular mean flength toY whichthe load Ycarryingy supported partcauses compression of i they loadl spring member, said automatic.. meanscomprising structure including, relativelyseparable pistonand cylindermembers one Withinthe other. and dening an. included fluid containingspace increasing and decreasing in volumewith increase and decrease ofrelative separation between said piston and cylinder members, -difierentonesof said piston and cylinder. members having. an operative connectionwith. therespective load carrying supportedk part: andtheoppositeend ofthe spring, and mechanical plunger prima meansincorporatedinthe-pistonand cylinsiructure and having at least. one .protrudingplungerengageable with the supporting partdurving reciprocal movement ofthe. supporting part thereto to operate the pump means for pumping to.change the volume' ofy the fluid in said fluid `containing space.

7. In combination,a load-carryingsupported part, a part for supportingsaid'load-carryingsupported -part;.a compression spring loadmember -anda shock absorber member .disposedaxially therewithinysaid members eachbeing mounted at vone end to said supporting part and'said shockabsorberr member having itsropposite end connected to said load-carryingsupported part, and means operatively associating the opposite end of4the `compression spring and load-carrying supported part and includingstructurecomprising. relatively separable piston and cylinder .membersone within the-other and -dening an ,included fluid containing spaceincreasing-and decreasingin volume with increase and decrease oftherelativeseparationv between said piston and cylinder members, diierentones of-said piston and cylinder members'havingv an operativeconnectionwith the respective load carrying supportedpart and the oppositefend-ofthe..spring,and pumping means incorporated in the piston and cylinderstructure and having at least one protruding plungerengageable witha.-portion.of. thesupv.porting part'during reciprocal. movement of thesupported lpart thereto to operate the pumping meansfor changing thevolume of Itheilfluid in saidfiiuid containing. space.

r8..In.a suspensionsystem, a vsupporting elemente. supported springhaving areceiving portion, and a load-carrying lift ,device engaging thereceiving portion. of .the Ispringlina.manner such, as to be,resiliently..mounted for. .reciprocative motionthereby under.conditionsincluding relatively high andrela'tively low spring' loadings,Y said .loadfcarrying lift deviceV having .associated Vtherewith power.pump means for adjustinglthe degree ofV liftfthereof, .and `including aplunger having a thrust-receiving portion engageableY by supportingelement during said reciprocative motion under atleast one of saidrelative spring loadings `for utilizing byV energy transformation thethrust forces of reciprocationvto .powerthe pump means and adjustthesaid degree oilift of the device.

9. In; a suspension system-a supporting. elef ment, a. supported springhaving avreceivingportion, and afload-carrying lift device engaging thereceiving portion of theV spring in a manner such as to be resiliently.mounted .for reciprocative motion, thereby -under conditions includingrela `tively high and relatively low spring loadings, said load-carryinglift device having associated there- -75 with. power pump means foradjusting the: degree of lift thereof, and including a plunger having athrust-receiving portion engageable by said supporting element duringsaid reciprocative motion under at least one spring loading forutilizing by energy transformation the thrust forces'of reciprocation topower the pump means and adjust the said degree of lift of the device,said load-carrying lift device comprising the combination with hydraulicjack and reservoir components for hydraulic fluid, of associated valvingcooperating with the power pump means to effect transfer of fluid fromat least one of the components to the other.

10. In a suspension system, a supporting element, an end-supported coilspring having a receiving portion adjacent the opposite end thereof, atelescopic shock absorber disposed within the spring and having an endin the vicinity of said opposite end of the spring, and a load-carryinglift device containing an hydraulic chamber and engaging the receivingportion of the spring and said end of the shock absorber in a mannersuch as to be resiliently mounted for damped reciprocative motionthereby under conditions including relatively high and relatively 10 lowspring loadings, said load-carrying lift device having associatedtherewith power pump means for adjusting the degree of lift thereof, andincluding a plunger having a thrust receiving portion engageable by saidsupporting element during said reciprocative motion under at least oneof said relative spring loadings for utilizing by energy transformationthe thrust forces of reciprocation to power the pump means and adjustthe said degree of lift of the device, said hydraulic chamber beingcooperatively disposed adjacent said shock absorber and power pump meansto serve as reservoir in common.

JOHN P. BUT'IERFIELD.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 2,379,012 Lee June 16, 19352,021,043 Bedford Nov. 12, 1935 2,361,575 Thompson Oct. 31, 1944

